1. Technical Field
The present invention relates to a forming method for a film pattern, a device, an electro-optical apparatus, an electronic apparatus, and a manufacturing method for an active matrix substrate.
2. Related Art
For example, a photolithographic method is widely used as a method for manufacturing wiring or the like which is to be arranged in a predetermined pattern for use in an electronic circuit or an integrated circuit or the like.
In such a photolithographic method, large scale manufacturing devices such as a vacuum device, an exposure device, and the like are required.
In addition, there is a problem in the case in which a predetermined pattern including wirings or the like is formed by using such devices as described above, a complicated process is required, and the efficiency of utilization of the material is also only a few percent and almost all of the original material must be discarded so that the manufacturing cost increases.
By contrast, a method has been proposed of manufacturing wiring or the like in a predetermined pattern upon a substrate by using a liquid drop ejecting method, i.e., a so-called ink-jet method, in which a liquid material is ejected from a liquid ejection head in the form of liquid drops.
For example, in Japanese Unexamined Patent Application, First Publication No. H11-274671 and Japanese Unexamined Patent Application, First Publication No. 2000-216330, there are disclosed a forming method for wirings or the like in a predetermined pattern upon a substrate by employing an ink-jet method.
With regard to this ink-jet method, a liquid material (a functional liquid) for the pattern is deposited directly upon the substrate in a predetermined patter, and thereafter heat processing or laser irradiation is performed, so as to form the desired pattern.
Therefore, in this method, no photolithographic process is required, this process is simplified. Thus, since it is possible to deposit the material directly in the pattern position, the amount of material used for this process can also be reduced.
Incidentally, the increase the density of circuits incorporated in various devices has progressed remarkably in recent years. For example, in the case of wiring, there has been a growing demand for further miniaturization and for the wiring to be made finer.
However, in the pattern forming method which employs the above described liquid drop ejecting method, it has been difficult to form a minute pattern in a stable manner, because the liquid drops which have been ejected tend to spread out upon the substrate after ejected.
In particular, in the case in which the pattern is an electrically conductive film, accumulations of liquid (bulges) is occurred (formed) due to the above spreading out of the liquid drops, and there is concern that there is occurrence of some inconvenience such as broken wiring or short-circuiting or the like.
In addition, as disclosed for example in Japanese Unexamined Patent Application, First Publication No. 2005-12181, there has been proposed a technique employing a bank structure which includes a wide wiring formation region having relatively large width, and a minute wiring formation region connected to the wide wiring formation region.
With regard to this technique, the functional liquid is ejected into the wide wiring formation region, the functional liquid is flowed into the minute wiring formation region due to a capillary phenomenon so that a minute wiring pattern is formed.
However, in the case in which the difference between the width of the minute wiring formation region and the width of the wiring formation region into which the functional liquid is ejected becomes large, since the functional liquid flows along the banks which demarcate the wide wiring formation region in generally, accordingly the amount of the functional liquid which flows into the minute wiring formation region due to the capillary phenomenon may be undesirably insufficiently.
Thus, there is a problem in that the thickness of the minute wiring pattern which is formed by the above described method is undesirably thinner than that of the other wiring pattern.
Accordingly, for example, a method has been considered of achievement to increase the thickness of the minute wiring pattern by narrowing down the width of one portion of the wide wiring formation region, thereby increasing the amount of functional liquid which flows from the wide wiring formation region into the minute formation region.
However, in the case in which the width of a portion of the wiring formation region (the pattern formation region) is narrowed down and the amount of the functional liquid which flows into the minute wiling formation region (the first pattern formation region) is increased in this manner, it is difficult to adjust the amount of the functional liquid that flows into in an appropriate manner.
For example, if the functional liquid excessively flows into the minute wiring formation region, then the thickness of the minute wiring pattern becomes thick, as compared to that of the other portions of the wiring pattern, and a difference of thickness is undesirably occurred between the minute wiring portion and the other portions of the wiring pattern.
Thus, in the case in which this technique is applied to, for example, forming a gate wiring and a gate electrode connected to the gate wiring, then it is undesirably difficult to obtain a stable transistor characteristic, due to the thickness being different between the gate wiring and the gate electrode.